Wireless sensors, for autonomous remote monitoring, are used extensively and their data analyzed in industrial and commercial applications for monitoring and to improve processes. Sensors are also used in consumer devices to make the particular device work better such as an accelerometer in an iPhone. However, direct use of sensors for consumer applications by the consumer is often limited to measuring and displaying a sensor readout on the sensor device such as in a temperature sensor with a digital display. Using sensors in consumer applications beyond a simple digital readout with capabilities as used in the commercial application will increase the cost of the sensor device significantly.
Wireless transmission of electromagnetic radiation communication signals has become a popular method of transmitting RF signals, such as cordless, wireless, and cellular telephone signals, pager signals, two-way radio signals, use of WiFi wireless for data transmissions in homes and offices etc. Sensors with wireless capabilities are common place while battery powered wireless sensing, though recent, have been growing because it is a more cost effective solution compared to wiring up all the sensors. There are many battery powered wireless sensors available commercially and even some of these are available for consumer applications though these wireless sensors require installing a receiver or a receiver network, which increases the cost considerably, and often times require experts to make the complete monitoring system work.
802.11 based wireless systems (also known as WiFi) are ubiquitous and routinely used to connect to the internet. A significant advantage of WiFi wireless networks compared to other wireless technologies is the widespread WiFi infrastructure in place, the much better security and availability of low cost receivers in any electronic store. However, WiFi sensors have not been common because of the high power requirements of a WiFi wireless transceiver. A battery powered WiFi transceiver will last less then 8 hours of continuous operations using a Lithium AA battery, therefore battery powered WiFi based sensors in the consumer space is rare and the few that are available have very low battery life. In recent years with some innovations low power WiFi based sensors have become available and are being used in a myriad of applications from environmental monitoring, to monitoring of freezers and refrigerators in hospitals or food storage applications, to energy monitoring. The sensors can last up to 3 years or more using a single AA Li battery with 2000 mA.Hr capacity while measuring and transmitting the sensor data wirelessly every minute. These battery powered WiFi sensors are being used in health care and food storage monitoring and few other commercial applications.
A smartphone, which is a mobile phone, with advanced computing ability, has not been a platform for sensor communications though the capability exists. Recent products such as the iCelsius convert the iPhone into a data logger for measuring temperature and relative humidity. However, these sensors are tethered to the device and not wireless. A cost effective sensor solution for consumer application with remote monitoring capability is possible by using WiFi based wireless sensors that will work with the smart phones and the cloud based computing on the internet; such an integration of these three platforms has not been achieved in such a way that the user does not have to intervene to make it all work seamlessly.